news sciences: Sun in zodiac constellations, 2017

Ophiuchus in Urania’s Mirror, a boxed set of 32 constellation cards first published in 1824. Image via www.ianridpath.com.

Ophiuchus the Serpent Bearer is not an astrological sign, but it is one of the 13 constellations of the zodiac. In 2017, the sun crosses into Ophiuchus on November 30. Image via www.ianridpath.com.

You might know that the real sun in the real sky does not appear in front of a constellation of the zodiac within the same range of dates you’ll see listed in astrological horoscopes. That’s because astrology and astronomy are different systems. Astrologers typically indicate the sun’s position with signs while astronomers use constellations. We were asked for:

… a list of the constellations that fall on the ecliptic with the exact degrees.

And we’ve located this information in Guy Ottewell’s Timetable of astronomical events. Below, you’ll find the dates for the sun’s entry into each zodiacal constellation during the year 2017, plus the sun’s ecliptic longitude – its position east of the March equinox point on the ecliptic – for each given date.

We are using the boundaries for the zodiacal constellations established by the International Astronomical Union in the 1930s.

The sun resides at a longitude of 0^o on the ecliptic at the March equinox. The sun is at 90^o ecliptic longitude at the June solstice, 180 ^o ecliptic longitude at the September equinox and 270^o ecliptic longitude on the December solstice. Image via Wikipedia

Date of sun’s entry into each zodiacal constellation (and corresponding ecliptic longitude):

Dec 18, 2016: Sun enters constellation Sagittarius (266.57^o)

Jan 19, 2017: Sun enters constellation Capricornus (299.69^o)

Feb 16, 2017: Sun enters constellation Aquarius (327.87^o)

Mar 11, 2017: Sun enters constellation Pisces (351.55^o)

Apr 18, 2017: Sun enters constellation Aries (29.07^o)

May 14, 2017: Sun enters constellation Taurus (53.45^o)

Jun 21, 2017: Sun enters constellation Gemini (90.41^o)

Jul 20, 2017: Sun enters constellation Cancer (118.24^o)

Aug 10, 2017: Sun enters constellation Leo (138.16^o)

Sep 16, 2017: Sun enters constellation Virgo (174.14^o)

Oct 31, 2017: Sun enters constellation Libra (217.78^o)

Nov 23, 2017: Sun enters constellation Scorpius (241.12^o)

Nov 30, 2017: Sun enters constellation Ophiuchus (248.02^o)

Dec 18, 2017: Sun enters constellation Sagittarius (266.59^o)

Source: Timetable of astronomical events

Earth-centered ecliptic coordinates as seen from outside the celestial sphere. Ecliptic longitude (red) is measured along the ecliptic from the vernal equinox at 0^o longitude. Ecliptic latitude (yellow) is measured perpendicular to the ecliptic. Image via Wikimedia Commons

Constellations of the zodiac:

Dates of sun’s entry into astrological signs versus astronomical constellations. Chart and more explanation at Guy’s Ottewell’s blog. Used with permission.

Bottom line: Sun-entry dates to zodiac constellations in 2017, using boundaries for constellations set by International Astronomical Union in 1930s.

Click here to learn dates the sun enters each sign of the zodiac.

What is the zodiac?

from EarthSky http://ift.tt/2idxFEY